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OLIVIA is a MFSK mode designed for QRP and QRM (due to a large bandwidth, up to 1000 Hz) transmissions. It uses Walsh-Hadamard functions, an interleaver and a scrambler which makes it robust. The minimum ratio Signal-to-Noise ratio is about - 12 dB (in the standard mode).
Creator : Pawel Jalocha SP9VRC in 2005
Description of the standard mode ("default mode"):
Baud rate : 31.25
Speed : 2.44 characters/sec so 24 wpm
Modulation : FSK 32 tones (5 bits arranged in a Gray form), with a shift between tones of 31.25 Hz (1000 Hz bandwidth). A "block" is defined as composed of 64 symbols of 5 bits (in other words it is a matrix of 64 columns (following the time) on 5 lines). Each of the 5 block lines of this block corresponds to a character which has been encoded, on a 64 bits vector, using a Walsh-Hadamard transform to provide a high level of redundancy.

Note: the implicite used matrix is 128x64dimension, the 64 first lines are the 64 standard orthogonal combinations of the Hadamard matrix. The 64 next lines are their opposite. So any couple of lines are either orthogonal (scalar product=0) or biorthogonal (scalar product<0).
Reception mode : sensible to the side (USB or LSB), USB is recommended
Shape of pulse : specific shape (between a Hanning window and a rectangular window)
Character set : ASCII 7 bits (128 characters)
Bandwidth : 1000 Hz
Synchronization : automatic using the signal
Correction code : no
Convolution code : no
Interleaving : yes, spreading of 5 bits "vertically" in the block,

Scrambling : yes, with a 64 bits sequence applied on each line of the block but with a delay of 13 bits between two successive lines.
Drift tolerance : 30 Hz/mn according to signal-to-noise ratio,
Pmean/Ppeak : 0.76
Lowest S/N : - 12 dB

Olivia modes decoded by Multipsk
This program decodes 6 Olivia modes, which are the modes:

* "8-250": "Slow" 8 tones, bandwidth=250 Hz, speed=31.25 bauds, 14.6 wpm, lowest S/N=-14 dB,
* "16-500": "Average" 16 tonalités, bandwidth=500 Hz, speed=31.25 bauds, 19.5 wpm, lowest S/N =-13 dB,
* "32-1K" ("Standard" default mode): 32 tonalités, bandwidth=1000 Hz, speed=31.25 bauds, 24.4 wpm, lowest S/N =-12 dB,
* "8-500": "Normal" 8 tonalités, bandwidth=500 Hz, speed=62.5 bauds, 29.3 wpm, lowest S/N =-11 dB,
* "16-1K": "Fast" 16 tonalités, bandwidth=1000 Hz, speed=62.5 bauds, 39.1 wpm, lowest S/N =-10 dB,
* "4-500": "Fast 2" 4 tonalités, bandwidth=500 Hz, speed=125 bauds, 39.1 wpm, lowest S/N =-10 dB,
* "4-250": "Average 2" 4 tonalités, bandwidth=250 Hz, speed=62,5 bauds, 19,5 wpm, lowest S/N =-12 dB,
* "8-1K": "Very fast" 8 tonalités, bandwidth=1000 Hz, speed=125 bauds, 58.6 wpm, lowest S/N =-7 dB.

Note: it exists 40 Olivia modes (among which 5 are decoded by Multipsk), from 8 to 256 tones and from 125 to 2000 Hz of bandwidth. All are conceived in the same way.



Mode Menu
OLIVIA
Mode Audio Sample
FFT Window Screenshot
Olivia1k